Elucidating the Role of Environmental Turbulence in the Lifecycle of Marine Fog Using the Novel Super Combo Probe

Marine fog poses many challenges to transportation, emergency response and defense, as it significantly reduces visibility. Understanding and accurately predicting the lifecycle of fog is therefore imperative for seafaring, aviation, and directed energy applications. However, simulating and predicting the onset, duration, and dissolution of sea fog remains a challenge, due in part to the sensitivity of the lifecycle of fog to microphysical processes, including the physicochemical properties of aerosols on which fog droplets develop and atmospheric surface-layer turbulence. As part of the Fog and Turbulence Interactions in the Marine Atmosphere (FATIMA) campaign, a novel super combo probe was deployed to capture simultaneously the velocity and temperature fluctuations down to the microscales during both clear and foggy conditions for the first time. Using this data, the role of Kolmogorov eddies—which encapsulate the fog condensation nuclei—in fog droplet activation and growth is investigated. The classical Köhler analysis is extended to include viscous-convective straining motions of Kolmogorov eddies, and it was found that droplet equilibrium is possible at a radius explicitly determined by the turbulent kinetic energy dissipation rate.